


Day Fifteen

by FellQueen (Nikasha)



Series: Kinktober 2019 [15]
Category: Undertale (Video Game)
Genre: Caelum the Reaper/R00ts, Kira the Error/Reaper, M/M, Masturbation, OC Au Sanses, Voyeurism
Language: English
Status: Completed
Published: 2019-10-16
Updated: 2019-10-16
Packaged: 2020-12-17 10:24:12
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,189
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21052835
Author URL: https://archiveofourown.org/users/Nikasha/pseuds/FellQueen
Summary: Day FifteenPrompt: VoyeurismPairing: Kira/Caelum





	Day Fifteen

**Author's Note:**

> Skipped day fourteen. Might post it later if I get caught up.
> 
> Kira is my own creation and Caelum is my friend Luna’s. She requested this and I was quite happy to oblige.
> 
> Kira is from a Reaper!Sans parent and Error!Sans parent. Caelum is from a different Reaper!Sans and R00ts!Sans (owned by kaminooniseika on tumblr.)
> 
> They are not related.
> 
> More info in end notes. Enjoy my self-indulgence~

Kira sat in his hammock, brow furrowed as he watched the white skeleton on the other side of the room. His boyfriend was bare, and the clean expanse of bone painfully tantalizing. “What are you doing?” he asked, voice tight.  
Caelum was smiling like usual, but there was a teasing tilt to it that set his bones on fire. He dragged his hand down his ribs and the front of his pelvis, almost purring. “Well, we can’t touch each other...but no one said we couldn’t watch.”  
Kira perked, the wavering glitches over his form sparking to life before settling again. “Watch?” he echoed breathlessly.  
“Mmh.” Caelum traced a finger over the inside of his femur. Kira’s mouth was watering. “We could always go to Reapertale, too, but this could be fun...right?”  
Kira had known Caelum for years now, but he still couldn’t hear even the slightest inflection of doubt in his tone. He did, however, know at this point how to interpret his words. “Yeah,” he said, hands gripping tightly to the sides of the hammock he had made with his own string. “Fun.”  
Caelum relaxed minutely. “Join me?” he asked plaintively, scraping his fingertips over his hipbone and licking his teeth.  
Kira looked up into empty sockets briefly before pushing himself out of the hammock. He settled on the floor, hands tucked safely into his hoodie pocket.  
Caelum smiled wider, waving to get Kira’s attention. “Pay attention to me.”  
“Ha-ard not to,” he murmured, wincing.  
Caelum nodded. “What do I need to do?” he asked.  
Kira blinked. He shifted nervously. “Nothing, you don’t need to do...anything.” He sighed a little and squared his shoulders. “But if you wanted to touch yourself...I wouldn’t complain.”  
Caelum snickered. His hand trailed back up to his ribs, tickling at the underside. “Sounds good to me.” His breath hitched.  
Kira’s left socket flared with magic. “Touch your spine. Dig your fingers into the gaps,” he murmured.  
“Seems more painful than nice,” Caelum said as he moved to obey. But when he pushed his fingers against soft cartilage, he flinched, jerking his hand away. “Oh.”  
Kira smirked. “Go on.”  
Caelum looked up at him, the magic in his face brightening. “Uh...ok.” His voice was low, both aroused and almost reverent as he did it again, a squeak coming from him as he bit back a groan.  
Kira felt his magic surge in response to the vulnerable noise, leaning forward.  
Caelum glanced up. He slid his hand lower, curling around the front of his pelvis and making him buck. “Kira,” he breathed.  
Kira’s breath stuttered. “Gods, I wish I could touch you right now,” he blurted out.  
Caelum laughed and spread his legs, giving Kira a fantastic view of the entrance he had formed. He was already dripping. “Maybe later~”  
Kira cut out into darkness. It was like he had been punched in the dick. When he returned, the glitches fading from his line of sight, Caelum was watching him patiently, finger trailing over the outside of his cunt. “There you are,” he said happily.  
Kira flushed. “S-Sorry,” he mumbled.  
His boyfriend laughed. “It’s okay, I figured that might happen.” He was still teasing around the outside of his entrance, leveling Kira with a lidded look. “So?”  
That simple, almost challenging, question grounded him. He glanced at the questing digits. “Okay. Press one in.”  
Caelum obliged, pressing his teeth together. “That...feels weird.”  
Kira smiled a little. “You’re so noisy.”  
He was, his cunt making wet sounds as his finger slid in and out of him slowly and he kept making little whimpers that Kira wasn’t sure he knew he was making.  
“Another.” Kira moved his arm, crossing it across his lap to hide the glow in his pants.  
Caelum was panting, leaning back on one elbow to watch Kira’s reactions. His ribcage was shaking as he breathed. His rhythm faltered as he pressed another finger into himself. “K-Kira...”  
Kira’s shoulders hunched. This no-touching rule was difficult. Even if he couldn’t touch with his hands, they usually found other ways to interact. Yet...there was something so nice about watching Caelum make himself feel good without Kira’s direct input. Like he was watching a special show, just for him.  
He supposed he was.  
“More,” he purred, pressing his arm against the formed length in his clothes. He could wait. He would wait.  
Caelum moaned and curled his fingers. “Not...quite there,” he complained absently, twisting a little to try to get a better reach. It was appalling how flexible he was. Kira throbbed. Caelum must have found the spot because he suddenly yelped, hips thrusting sharply into the air as his dick formed, magic gathering from his pelvis to form the shape in record time. He was leaking, precum sliding down the side of his magic.  
Caelum grinded against his own fingers, panting and groaning incoherently. His free hand wrapped around his spine, digging in like Kira had told him earlier.  
It was a buffet of sights and sounds, and Kira had his length out of his pants and in his hand before he could stop himself. He tried to keep it slow, wanting to keep his full attention on Caelum, but his intentions went out the window when the pale skeleton introduced two additional fingers at once, arching into it. He was moaning Kira’s name, sockets fluttering as he writhed under his own touch.  
Even as Kira’s hand sped up, he gripped onto his leg, trying to keep himself in some semblance of control. It was difficult.  
“Kira, please,” Caelum suddenly gasped, and let go of his spine. He gave a heartfelt groan, legs twitching as he thrust his fingers into himself. “More.”  
“More?” Kira echoed, startled. He laughed weakly. “Cael, I—“  
Caelum abruptly stopped, a lewd sound stalling out Kira’s thoughts as he withdrew his fingers. Caelum shifted to his knees and crawled over to Kira, pressing his forehead to his shoulder a bit awkwardly and nudging until he got the picture and laid back on the floor. The pale skeleton straddled his hips, careful not touch bone directly, and sank down onto Kira’s dick without warning.  
They both moaned in satisfaction. Kira’s hands twitched until he shoved them back into his pocket to stop the urge to grip and touch. Caelum pressed his hands against the outside of Kira’s jacket lightly, using mostly his legs as he started riding for all he was worth.  
After playing around, neither of them were going to last. Caelum broke first with a wrenching cry, back curving beautifully and head tossed back.  
“Cael,” Kira said in awe and followed a moment later, enthralled with the feeling of filling Caelum with his magic.  
As they caught their breath, they stared at each other, enraptured.  
“I love you,” Kira murmured. He couldn’t touch, but the words were filled with emotion to make up for it.  
Caelum smiled. “I love you, too.” A pause. “Wanna head to Reapertale for round two?”  
Kira twitched where they were still connected. “Fuck yeah, let’s go.”  
His hands itched to touch his lover until he fell to pieces.

**Author's Note:**

> List used: https://twitter.com/idek_uggy/status/1178349575725174786?s=21
> 
> Tomorrow is fisting
> 
> About Kira and Caelum: as children of a Reaper!Sans they are cursed. Kira deletes the code of absolutely anything he touches with his hands. Caelum drains the life from whatever he touches. He usually wears gloves to mitigate that.


End file.
